Nobody has commented yet. I haven't commented because I really don't have an answer but I do have a point to make.

First I doubt any of the torsos were directly connected to JtR.

I think Whitehall may be connected to other torsos that were left in public places, surely to create outrage and get attention. That is the commonality more than method of killing, etc., IMO

The deeper we dig into murder in general the more we see killers doing similar things. Walter Turner in Yorkshire did things similar to the torso cases, to his known child victim and possibly an earlier victim. He was at least a good part of the way to creating body parts. (If he did not kill Johnny Gill then there were two extremely perverted child killers in a three year period in a fairly small area.)

Most of us cringe at the thought of dismembering a body but once the line of perversion is crossed it seems anything goes. Sane people want to connect the dots to find one or two perverted killers. Sadly it seems there are more of these creeps operating at any one time than sane people want to contemplate.

Then taking into account the practical restrictions of the LVP, cutting up unwanted bodies makes sense. Folks didn't have cars to transport and dump whole bodies. Maybe bodies were reduced to torsos and other parts more frequently than we know, maybe even bodies that died of natural causes. Except Whitehall, Pinchin Street and a few others seem to be calculated to get maximum attention and outrage.

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If the shawl doesn't fit, you must acquit.~~Henry Flower, Casebook post